Panasonic CS-PC12QKH, Service Manual

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67
RPM shift
+0
+20
+40
+70
(ID temp) Pipe
6.0°C
4.0°C
2.0°C
5.0°C
7.0°C
3.0°C
Compressor starts for ≥ 5 minutes
▲ T ≤ 2.5°C for 2 minutes
Compressor
OFF
Compressor
restart
▲ T = Intake air temperature – Indoor heat exchanger temperature
(For PC9/12QKH)

The current fan speed will change to freeze prevention speed after 70 seconds compressor on. The fan speed
will be increased according to the indoor pipe temperature the figure below:
14.6 Compressor Reverse Rotation Protection Control

If the compressor is operating continuously for 5 minutes or longer and the temperature difference between
intake air and indoor heat exchanger is 2.5°C or less for continuously 2 minutes, compressor will stop and restart
automatically.

Time Delay Safety Control is activated before the compressor restart.

This is to prevent compressor from rotate reversely when there is an instantaneous power failure.

If this condition happens continuously for 5 times within 50 minutes, unit will turns OFF with TIMER indicator
blinks.

The 5 Times counter can be reset when either one of the following condition happen:
o
Unit is OFF by remote control or AUTO OFF/ON button.
o
Indoor intake temperature – Indoor piping temperature > 5°C for 1 minute or more.
o
Operation mode change.

The unit could be ON by pressing OFF/ON button at remote control but the TIMER LED will continue blinking.

TIMER LED blinking will be reset if:
o
Indoor intake temperature – Indoor piping temperature > 5°C for 1 minute or more.
o
Power supply reset.
14.7 Dew Prevention Control

To prevent dew formation at indoor unit discharge area.

This control will be activated if:
o
Cooling mode.
o
Remote Control setting temperature is less than 25°C.
o
Fan speed is at CLo.
o
Room temperature is constant (±1°C) for 60 minutes (For 9/12QKH series) and 30 minutes (For
18/24/28QKH series).
o
Compressor is continuously running.

Fan speed will be adjusted accordingly in this control.
o
Fan speed will be increased slowly.

Dew prevention stop condition
o
Remote control setting temperature is more than 25°C.
o
Fan speed is not set to CLo.